Encarsia dongbeiana Li & Geng, 2017

Encarsia dongbeiana Li & Geng , sp. nov.

Figs 2–17 View FIGURES 2 – 6 View FIGURES 7 – 10 View FIGURES 11 – 17

Type material. Holotype. ♀ [on slide, NEFU]: CHINA, Liaoning Province, Anshan City, Qianshan Mountains, Xianrentai , 20.IX.2015, Hui Geng , Xin-Yu Zhang , Ye Chen , sweeping.

Paratypes. 1♀, 1♂ [on slides, NEFU], same data as holotype ; 4♀, 4♂ [on slides, NEFU], CHINA, Heilongjiang Province, Mudanjiang City, Heixiazigou, 26.VIII.2015, Hui Geng , Yan Gao , Zhi-Guang Wu , sweeping ; 1♀, 2♂ [on slides, NEFU], CHINA, Jilin Province, Wangqing County, Daxingou Town, Longshui Village , 24.VIII.2015, Hui Geng , Yan Gao , Zhi-Guang Wu , sweeping.

Diagnosis. Female. Length, mesosoma plus metasoma, 0.57–0.71 mm. Head mainly yellow with postocellar bars dark brown and two short oblique bands above occipital foramen brown ( Figs 2, 3 View FIGURES 2 – 6 ). Mesosoma and metasoma entirely dark yellow with only pronotum pale brown. Mid lobe of mesoscutum with 8 or 9 setae; placoid sensilla on scutellum moderately separated ( Fig. 7 View FIGURES 7 – 10 ). Fore wing ( Fig. 5 View FIGURES 2 – 6 ) 2.52–2.74× as long as wide, marginal fringe 0.26–0.3× as long as wing width. Mid tibial spur 0.54–0.62× as long as corresponding basitarsus ( Fig. 8 View FIGURES 7 – 10 ). Ovipositor slightly exerted, about as long as mid tibia; third valvula 0.40–0.46× as long as second valvifer ( Fig. 9 View FIGURES 7 – 10 ).

Male. Mostly brown with some paler parts. Antenna with last two flagellomeres partly fused ( Fig. 12 View FIGURES 11 – 17 ). Genitalia 0.75–0.84× as long as mid tibia.

Description. Female. Holotype. Length, mesosoma plus metasoma, 0.61 mm. Head yellow except postocellar bars dark brown and two short oblique bands above occipital foramen brown. Antenna ( Fig. 4 View FIGURES 2 – 6 ) dark yellow with radicle and scape pale yellow and distal flagellomere brown. Mesosoma and metasoma entirely dark yellow with only pronotum pale brown. Wings ( Figs 5, 6 View FIGURES 2 – 6 ) including venation hyaline. Legs completely yellow.

Head ( cf. Fig. 2 View FIGURES 2 – 6 ), as wide as mesosoma in dorsal view. Ocelli forming about an obtuse triangle, POL<OOL. Stemmaticum ( cf. Fig. 3 View FIGURES 2 – 6 ) with transversely rugose sculpture. Mandible with two teeth and a truncation ( cf. Fig. 2 View FIGURES 2 – 6 ). Radicle (R), scape (S), pedicel (P), and 6 flagellomeres with the following ratios of length to width: R: 2.91, S: 3.59, P: 1.55, F1: 1.78, F2: 2.1, F3: 2.2, F4: 1.96, F5: 1.74 and F6: 1.83; relative lengths of R–F6 to length of F1: R: 1.00, S: 2.63, P: 0.88, F1: 1.00, F2: 1.25, F3: 1.38, F4: 1.38, F5: 1.25, and F6: 1.31; flagellomeres with the following numbers of longitudinal sensilla: F1: 1, F2: 2, F3: 2, F4: 3, F5: 3, F6: 3.

Mesosoma 0.68× as long as metasoma. Mid lobe of mesoscutum ( Fig. 7 View FIGURES 7 – 10 ) with 9 setae, each side lobe of mesoscutum with 3 setae. Distance between placoid sensilla on scutellum approximately 4.4× maximum width of a sensillum. Distance between anterior pair of scutellar setae 1.64× distance between posterior pair. Fore wing ( Fig. 5 View FIGURES 2 – 6 ) 2.59× as long as wide, costal cell with 10 short setae, basal cell with 6 setae, marginal vein with 6 setae along anterior margin; marginal fringe 0.27 × as long as wing width. Mid tibial spur 0.58× as long as corresponding basitarsus, the latter 0.38× as long as mid tibia. Hind tibia 1.04× as long as mid tibia ( Fig.8 View FIGURES 7 – 10 ).

Metasoma ( Fig. 9 View FIGURES 7 – 10 ) with petiole ( Fig. 10 View FIGURES 7 – 10 ) sculptured. T2–T7 with 1+1, 1+1, 1+1, 2+2, 1+4+1 (4 between cercal plates) and 4 setae, respectively. Ovipositor ( Fig. 9 View FIGURES 7 – 10 ) slightly exerted, apparently originating from base of T3, 1.03× as long as mid tibia, and 0.75× as long as mid tibia and basitarsus combined. Third valvula 0.46× as long as second valvifer.

Male. Essentially similar to female, differing mainly in colour, antennal structure and genitalia. Head ( Fig. 11 View FIGURES 11 – 17 ) yellow except malar sulcus infuscate, a stripe at level of occipital foramen brown, and postocellar bars dark brown. Mesosoma ( Fig. 13 View FIGURES 11 – 17 ) largely yellow with pronotum, mid lobe of mesoscutum anteriorly and mediolongitudinally, axillae and propodeum brown. Metasoma brown to dark brown with T6 posteriorly and T7 yellow. Antenna ( Fig. 12 View FIGURES 11 – 17 ) dark brown with abundant longitudinal sensilla on all flagellomeres, last two flagellomeres partly fused. Genitalia ( Fig. 17 View FIGURES 11 – 17 ) 0.75–0.84× as long as mid tibia.

Host. Unknown.

Variation. Length, mesosoma plus metasoma, 0.57–0.71 mm. Antenna dark yellow to yellowish-brown. Mesosoma and metasoma entirely dark yellow with pronotum, cercal plates and ovipositor stylet apically brown or pale brown. F1 0.94–1.14× as long as pedicel, without or with 1 longitudinal sensillum. Fore wing 2.52– 2.74× as long as wide, marginal fringe 0.26–0.3× as long as wing width. Basal cell with 6–10 setae. Marginal vein usually with 6 or 7 (rarely 5 or 8) long setae along anterior margin. Ovipositor 0.99–1.09× as long as mid tibia, and 0.72–0.79× as long as mid tibia and basitarsus combined. Third valvula 0.4–0.46× as long as second valvifer.

Etymology. dongbei = the Chinese word for northeast; and refers to the distribution of the species in the northeastern part of China.

Comments. E. dongbeiana is similar to E. aferi Schmidt & Polaszek in having the head and body mostly yellowish, but differs from the latter in: mesosoma and metasoma with only pronotum brownish ( vs with some brownish patches on mesosoma, petiole and faint transverse band on T1); marginal fringe of fore wing 0.26– 0.3× as long as wing width ( vs 0.2–0.21×); distance between anterior pair of scutellar setae 1.4–1.64× distance between posterior pair ( vs 1×); ovipositor 0.99–1.09× as long as mid tibia ( vs 0.85–0.91×); third valvula 0.4– 0.46× as long as second valvifer ( vs 0.3–0.33).

Encarsia dongbeiana also resembles those E. melanostoma Polaszek & Hernández with a completely yellow metasoma (colouration variable in melanostoma as noted in original description), but differs from the latter in different antennal formula, 1,1,4,2 ( vs 1,1,3,3), presence of internal sculpture in the cells forming reticulation on mesoscutum ( vs absent), pale clypeus and malar sulcus ( vs dark) and more distantly placed anterior pair of scutellar setae than that between posterior pair, 1.4–1.64× ( vs 0.8–1.1×).